LED Anchor Light

[transmitterdan]

Originally Posted by cal40john

Internal circuitry provides for constant current consumption, regardless of voltage fluctuations from the source (11
to 15 VDC), meaning no flickering and longer LED life

Something doesn't sound right about that. Ideally current consumption should go down in proportion to increasing voltage. If current consumption stays constant with increasing voltage then power is being wasted somewhere and will cause increased heating. The voltage multiplied by current consumption should be a constant for best efficiency and long LED life.

[bmm32005]

So how does the Bebi Owl mount to the mast head? It looks like a PVC end cap with no mounting hardware. I wouldn't attache it to a halyard and pull it up due to it banging around while on anchor.

[noelex 77]

There are a number of mounting options shown on the website here:
(Including how to fit it to the common Hella and Aquasignal units)

Bebi Electronics-Installing Marine LED Reading, Navigation and Running Lights!

Ii can be easily glued into standard water pipe which makes the mounting options quite versatile.

I am not a fan of using these types of lights for other navigation lights. The colours and sector cut off is never accurate.
There are no such concerns with anchor lights.

[ohdrinkboy]

Originally Posted by scoobert

i have not had a daylight sensor that lasted more then a few years, i am always leery of those. just make sure it keeps coming on if you use it as the primary anchor light.

I've got 8 years on my Davis LED sensor.....darn, now I may have jinxed it.

[colemj]

Our Davis light sensor didn't make it a year.

The light sensor on our OGM Tricolor/anchor light lasted 5 years before being struck by lightning and its replacement has been working for 2 years.

Mark

[scoobert]

Originally Posted by ohdrinkboy

I've got 8 years on my Davis LED sensor.....darn, now I may have jinxed it.

failure rate is a funny thing.
take computer hard drives.
they run about 10,000 drives, for hours, and sample how many fail, and at what interval. then they tell you the MTBF based on that. my primarry hard drive has a MTBF of 1,000,000 hours. but it reality it may never boot up, or it may run 10,000,000 hours, or anywhere in between. all electronics are like this. when they print the circuits dust can contaminate the circuit, and you can have a quick failure....

[cal40john]

Originally Posted by transmitterdan

Something doesn't sound right about that. Ideally current consumption should go down in proportion to increasing voltage. If current consumption stays constant with increasing voltage then power is being wasted somewhere and will cause increased heating. The voltage multiplied by current consumption should be a constant for best efficiency and long LED life.

What is the required end result? Answer is constant current through the LED.

Think buck converter:
Buck converter - Wikipedia, the free encyclopedia

Now configure a buck converter to supply constant current rather than constant voltage:
Power Management - LED Lighting - LM3404HV - TI.com

[Paul Elliott]

Originally Posted by transmitterdan

Something doesn't sound right about that. Ideally current consumption should go down in proportion to increasing voltage. If current consumption stays constant with increasing voltage then power is being wasted somewhere and will cause increased heating. The voltage multiplied by current consumption should be a constant for best efficiency and long LED life.

If we're discussing the Bebi lights, they use (or did use, last I checked) a simpler linear constant-current driver rather than a switching-regulator design. This kept the cost down, and reduced the potential for radio interference. Yes, it's less efficient power-wise, but at least in a 12V system the difference isn't too bad. It's still a huge power-consumption improvement over incandescent bulbs.

Most other LED nav-light designs use a switching LED driver where the input current drops as the voltage rises..

[edit: I see the question was about Dr. LED lights, and the LED current. Sorry. I am leaving my original post because someone might be interested in the internals of the Bebi lights.]

[noelex 77]

Originally Posted by Paul Elliott

Yes, it's less efficient power-wise, but at least in a 12V system the difference isn't too bad. It's still a huge power-consumption improvement over incandescent bulbs.
.

Bebi do use a less efficient driver, but surprisingly in practice the total light uses less power than the opposition.
The Owl uses 0.065A which is about half the consumption of most typical led 2 mile anchor lights.

Emitter efficiency plays a bigger role than driver effeciency.

[transmitterdan]

Originally Posted by cal40john

What is the required end result? Answer is constant current through the LED.

Yes, but that is not necessarily the same as constant current consumption from the battery. A switching regulator will draw constant power.

I agree with another post that constant current linear regulators may generate less interference but the heat dissipated will be much higher at typical battery voltages than at minimum voltage. For example, a linear regulated LED system that drives a 250mA LED string may dissipate 2.75W at 11V. But at a typical charging level of 13.8V that becomes 3.5W. All the DC input power has to go somewhere either as heat from the LED or heat from the linear regulator. I also agree it is still less heat than incandescent for sure.

[Nicholson58]

Originally Posted by SailPenelope

Marinebeam claims their bulbs are not as sensitive to voltage changes as the others......read about it on their website.

BIBI is good stuff. I have several of their lights, IMTRA, Marine Beam, Signalmate and a couple others. You are correct about the voltage variations. That is why one does not use automotive LEDs designed to operate perfectly at 13.5 volts with the alternator running. They drop off at low voltage and may have a short life on a boat charger. The high end LED replacements are PWM (pulse width modulated) with a high speed switching circuit. The % on versus off time is controled to yield the correct forward CURRENT, no matter the voltage. Mine work form 9 to 50 VDC. Read the primers at BIBI's site and at Marine Beam.

On the anchor light, I also added a solar only light such as you can get from West but for a lot less through Amazon. It is quite adequate.

[Ram]

My Bebe Owl, did not make one year before the auto sensor-on/off- went out, when I wrote the compney he said send it back for replacement, being that im sailing all over this is not easy to do so I still have it- used it with on off switch, lasted 1 more year now dead and not working at all-

[Nicholson58]

Originally Posted by Ram

My Bebe Owl, did not make one year before the auto sensor-on/off- went out, when I wrote the compney he said send it back for replacement, being that im sailing all over this is not easy to do so I still have it- used it with on off switch, lasted 1 more year now dead and not working at all-

Sorry to hear that. I'm sure that Michael at BIBI would be happy to find a way to help you. He has been great to work with for me. I asked for a special for my Windex and installed two, one on each Windex stalk powered from the mast lights. (MAIN & MIZZEN) They slip over the stalk and light the tabs better than daylight. I had to add a shield so the LEDs were not visible from the side. (plastic pipe thread protector.) These are powered when the mast light is on so no new wires.

[Rubikoop]

That is really slick.

[kentobin]

http://www.cruisersforum.com/forums/...ts-111109.html

I understand they have gone through a change in owernership with the company now being entirely owned by Fijians.

I hope the difficulculty contacting them is not indicative of a change in customer service which has always been exemplary in the past.

above comment by noelex 77 at link